The present invention relates to devices for winding long, flexible belt-shaped material, hereinafter referred to as "a web" when applicable. More particularly, the invention relates to a web winding device in which, in a multi-slit type winding operation, webs are continuously wound on cores and a web winding width can be readily changed as required.
The term "multi-slit type winding" is intended to mean a winding system in which a web of relatively large width is slit into web segments of relatively small width while being unwound from a stock roll and the webs are wound on cores. In addition, the term "a web winding width" is intended to mean the width of a web segment to be wound on a core.
A winding operation in which a web is slit into web segments while being unwound from its stock roll and the web segments are wound on their respective cores has been employed in various industrial fields. In the case where the web winding width is maintained constant, it is of course unnecessary to change the web winding width. However, if a variety of products or web rolls are to be manufactured, it is necessary to change the web winding width depending on the type of product.
A conventional multi-slit type winding device for performing a continuous winding operation requiring a web winding width change is shown in FIG. 1. In that device, cores 2, such as hollow paper cores, are mounted on winding shafts 1 and webs W are simultaneously wound on the cores 2. Upon completion of the winding, a chucking nose 3 which rotatably holds one end of each winding shaft 1 is retracted axially so that the other end of the winding shaft can be readily removed from the frame 5. Thereafter, each winding shaft 1, including a number of web rolls Wr mounted thereon, is removed from the frame 5 manually or by a mechanical force such as that of a crane or a fork lift and a new winding shaft 1 is mounted on the frame 5. Preparation for winding the web winding width in the conventional device is carried out completely manually.
The conventional device suffers from difficulties that the necessary work accompanying a web roll switching operation such as the removal of the web rolls Wr, the replacement of the winding shafts 1 and the mounting of the cores 2 is troublesome, and as the web winding width is changed manually, the work time required is quite high. Thus, the conventional device is not considered completely practical.
In order to eliminate the above-described difficulties, a so-called "turret type web winding device" has been proposed in the art. In the device, the frame 5 of the above-described device is modified so as to be rotatable, the frame 5 thus modified is provided with a plurality of arms holding plural winding shafts 1 and cores 2, and the web winding system is divided into three axial turrets, specifically three stations respectively having a core supplying section, a web attaching and winding section, and a product or web roll discharging section.
In this device, the web winding operation is carried out continuously by turning the turrets. Therefore, the device is much improved in efficiency compared with the web winding device shown in FIG. 1.
However, a turret type web winding device is still disadvantageous in the following points. In order to turn the turrets, the device requires a number of components such as rotary joints and slip rings and accordingly the device is intrication in construction and high in manufacturing cost. In the case of changing the web winding width, it is necessary to change the positions of all of the above-described arms. If the positions of the arms are changed manually, much time and labor are required. The arms may be moved automatically by turning ball screws as disclosed in the specification of Japanese Laid-Open Patent Application No. 28084/1975. However, it should be noted that it is considerably difficult to accurately arrange a number of ball screws for the turning arms.
Accordingly, an object of the invention is to provide a web winding device of simple construction in which all of the above-described difficulties accompanying a conventional web winding device have been eliminated, webs can be successively attached to and wound on cores, and the web winding width can be readily changed.